Refrigeration systems absorb ambient heat in the area of their evaporator and they release heat in the area of their condenser.
Heat-activated refrigeration systems differ from vapor-compression refrigeration systems in that their compressors are driven by refrigerant turbines, or the like. Refrigerant heat to activate the turbine is wholly or partially obtained from an external source. Prior art recognizes that excess energy to the compressor could be used at a power take-off shaft.
Examples of heat-activated refrigeration systems are taught by U.S. Pat. Nos. 2,486,034; 2,511,716; 2,737,031; 3,172,270 and 3,400,555.